The purpose of this research is to enable Walter Reed Army Medical Center (WRAMC) to participate in the activities of the Pediatric Division, Southwest Oncology Group (SWOG) in solving the problems of childhood malignancy. The primary objective will be to integrate local ideas, research, patient material, and local multimodal therapeutic expertise with other SWOG institutions and groups. A multimodality approach is utilized with the co-ordination of institutional expertise in chemotherapy, radiotherapy, surgery, pathology, immunology and clinical pharmacy. Chemotherapy includes the use of experimental and standard drugs. Primary specific aims are (1) to improve the induction rate and length of median remission in children with acute non-lymphocytic leukemia (ANLL) while minimizing the induction toxicity, (2) to improve the long-term survival of children with advance rhabdomyosarcoma) (RMS), (3) to assess the long-term effects of growth and sexual maturation in children with RMS, (4) to determine the effect of multimodality therapy on survival in specific sites of RMS, (5) to determine the effect of age and metastatic site on survival in IV-S neuroblastoma. Secondary specific aims are (1) to provide a multidisciplinary approach for the care of children with malignancy and their families, (2) to evaluate granulocyte function and support in the compromised host, and (3) to evaluate the length of infusion time as a variable in the Kinetics of moderate dose methotrexate.